Saturday, February 19, 2011


O.K. now this is a little weird on several fronts. Yesterday's Kitchener-Waterloo Record carried this story: "Ancient riverbed hints at big storehouse of water". So after reading this article why am I confused? First of all our surface water in Waterloo Region generally follows our surface topography. In other words you will notice that the Grand River flows GENERALLY from north of Waterloo Region (Dundalk) southwards until it discharges in Lake Erie at Dunnville. Our shallow or Upper Aquifers generally flow and discharge into all the little streams and creeks which end up in the Grand. Think of the Canagagigue here in Elmira, the Nith, the Speed River and Conestogo River. Granted with all the turning and twisting of all these rivers it is quite possible to have shallow aquifers literally flowing either north, south or east and west. Now I might be prepared to believe that eons ago the surface drainage from here swung easterly towards Lake Ontario versus southerly towards Lake Erie. So perhaps there are scattered patches of sand and gravel underground between here and lake Ontario.

For me the bigger problem is the alleged depth of these sand and gravel aquifers. This article claims that they are 80 metres underground. That's more than 250 feet for the metrically challenged. That is ridiculous. I have studied groundwater as well as geology for the past twenty plus years. I have carefully examined drilled boreholes and stratigraphic logs throughout Waterloo Region. Here in Elmira our overburden (sand/gravel/clay/silt) is approximately 100 feet (32 metres) thick. Then you hit bedrock. Just north and east of here in the Elora and Fergus area you can see outcrops of the Bedrock right at the surface. South of here in Kitchener-Waterloo again there are areas with the overburden 100 feet thick but nearer the Grand River this overburden thins quickly. Then in Cambridge you will find dramatically thinner overburden. This is why contrary to Kitchener, Waterloo and Elmira area, most of the Municipal wells in Cambridge are drilled into and screened in the limestone and dolomite Bedrock. Now you can see my problem. If this article suggested that these aquifers were fractured Bedrock Aquifers then 250 feet down wouldn't surprise me. But to claim that there are sand and gravel aquifers at that depth is astounding . It is possible that this article is simply very vague and not telling us that these sand and gravel aquifers are entombed within the Bedrock. Conversely I wonder if it's a simple typographical error. Could it be possible that these articles should have said that these aquifers are 80 feet below surface? Regardless the better technically informed one is, the more likely to find major errors in nespaper stories. This absolutely is not a general slam at papers or reporters. They are writers first and technical people second. Whatever the cause I do hope that future stories about this potential source of water will be clearer.

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